A simple Python script that can be used to find bugs in a software application by crawling a web URL:
This script uses the requests library in Python to send a GET request to the specified web URL and the beautifulsoup4 library to parse the HTML content of the page. Then it looks for specific tags or attributes that indicate a bug, in this example it looks for the presence of a tags with href attributes, and form tags. If the links or forms are not found, it prints out "No links found" or "No forms found" respectively.
It's important to note that this is just an example and the actual test methods and their implementation will depend on the web application you want to test and also you need to have requests and beautifulsoup4 library installed in your environment to run this script.
It's also important to note that this script is just a skeleton and it doesn't include the actual implementations of the methods, these methods should be implemented by the tester according to the web application under test.
Additionally, you may want to consider using a more robust web crawling and web scraping tools like Scrapy and Selenium for finding bugs in web applications.